الفهرس 
Impact of feeding habit on the anatomy and histology of the alimentary canal of two reptilian species
ABSTRACTOnly 14 pages are availabe for public view
 |  | from | 142 |  |  |
| | | from | 142 | | |
Abstract
The present study aimed to study the anatomical, histological and histochemical features of the gastrointestinal tract (GIT) of the Nile Crocodile Crocodylus niloticus and the Gecko Tarentola annularis. The straight oesophagus is lined with pseudostratified ciliated columnar epithelium with goblet cells in Crocodylus niloticus, while in Tarentola annularis the oesophagus is comparatively short cylindrical tube and lined with simple ciliated columnar epithelial and goblet cells. The oesophagus is devoid of found glands in both species.It leads to the stomach which consists of two portions, fundic and pyloric.The gastric mucosa consisted of the surface mucosal epithelium, lamina propria and gastric glands in Crocodylus niloticus, while in Tarentola annularis the gastric mucosa is composed of simple columnar cells and many tubular glands. The small intestine is differentiated into duodenum and ileum in both species.The mucosal epithelium of the small intestine is composed of two kinds of cells; absorptive cells and goblet cells with well developed intestinal glands in Crocodylus niloticus, while in Tarentola annularisthe small intestine is comparatively short, The absence of the intestinal glands is observed.The epithelial lining of the small intestinal mucosa is constructed of simple columnar cells and numerous scattered goblet ones. In Crocodylus niloticusthe large intestine is very short as represented only by the rectum.The mucosa is lined by the cylindrical epithelium with absorptive cells and goblet cells. While in Tarentola annularis the large intestine is formed of a very small blind sac of the caecum,the short tube of colon and the rectum.The lining of the large intestine is provided with goblet cells with only few simple columnar ones. Acid and natural mucopolysaccharides were detected in the gut mucosa. PAS positive matter is found in the entire alimentary tract. Proteins and nucleic acid is observed in the different regions of the alimentary canal